intranet and internet
The main problem is that there is two environments and both (wither we like it or not) have completely different requirements:
intranet: line of business applications, fixed cost, upgraded once every 3-4 years (if that) with maintenance releases about every other month. The client (however hard I try) will not pay for cross browser support, or pay to trace down a bug in firefox, opera or safari as it is not there operating environment....even ie8...the fact is its v tough to sell cross browser support to a customer with his eye on the bottom line figures and who has no focus on technology.
The internet: way easier to sell cross browser support as latest greatest tech is used in the wild, the customer has no option..its not an only ie universe out there...but still find it hard to sell firefox, opera and safari/chrome support...but i avoid developing ie only products for this...and i find it easier to dig my heals in.
I use fedora 11 and firefox at home (debian lenny and iceweasel on my netbook) but mozilla, google and opera really need to start pushing themselves into the intranet space...i cant sell there products into that space for them...no profit in doing that...i just get looked at for being unrealistic and not focusing on the 'needs of the customer' (a line that has been used to justify untold sin and folly) :)
anyways thats my perspective on why ie6 isnt dead yet (oh how i wish it was dead) and why companies now are crapping themselves about the eventual death of ie6 no matter how hard they hang onto it...
Im a developer and yes im guilty of writing ie6 websites for intranet apps, im now starting to find it easier to sell the idea that they should now target ie8 aswell as ie6 as it is slowly 'going to be replaced with service packs and security updates'...